Thousands of Victorians exposed to smoke drifting into their community from a burning coal mine have been offered free train trips out of town by the state government, which has announced an independent inquiry into the fire.

Peter Ryan, the state’s deputy premier and emergency services minister, said the inquiry would look at all questions being asked about the fire, but only after it had been extinguished and the residents were safe.

“When they are accommodated we’ll then move to the position of an independent inquiry,” he said.

The Hazelwood mine in the Latrobe Valley has been burning for nearly three weeks, blanketing Morwell in falling ash and smoke.

The state’s public transport minister, Terry Mulder, said the offer of return train tickets to anywhere in Victoria was a goodwill gesture for those wanting to escape the smokey conditions.

The response came after Morwell locals complained that the smoke was making their lives impossible and that the authorities had been slow to act.

Residents heckled authorities in Morwell during a media conference held on Friday to discuss the temporary relocation of people most vulnerable – preschool children, pregnant women and anyone with a pre-existing heart or lung condition.

“We can’t sleep, we can’t go outside, we can’t breathe,” Estelle Landy said through tears. “There’s people in the street wearing masks every day. Everyone here shows you there’s a problem and nothing’s done at all. They tell us to stay but we can’t. You can’t continue to allow this to happen.”

Chief health officer Dr Rosemary Lester said the advice for those deemed vulnerable was a precautionary measure.

Weekly government grants of up to $1,250 will be available to those deemed eligible for the duration people need to be away from their homes.

Lester said the effects of medium-term exposure to the smoke was unclear,and there had been no serious health problems in Morwell as yet.

Fire Services commissioner Craig Lapsley said in the best case it would be another 10 days before the fire stopped sending significant smoke and ash over Morwell but authorities are concerned about two hot and windy days expected next week.

The Victorian premier, Denis Napthine, urged people to follow the chief health officer’s advice but said there was no compulsion for people to relocate.

The state opposition leader, Daniel Andrews, called on the federal government to take over, saying the Napthine government had botched its response.

Andrews said confusing advice was given to residents and an information centre was only set up on Friday.

“So inept, so incompetent has this government’s response to unfolding disaster been, I think the people of Morwell would be right to say perhaps Dr Napthine just doesn’t care about us,” he said.

The fire has forced a judge to twice move a criminal trial 50km away to Sale, while Australia Post has suspended delivery to Morwell street addresses. Several schools, kindergartens and childcare centres have closed or relocated to nearby towns.